1. Field of the Invention
The invention relates to connectors for joining together the ends of flue gas conduits of the type used for venting smoke and flue gases to the atmosphere.
2. Description of Related Art
U.S. Pat. No. 4,874,191 discloses a connection which utilizes a clamping ring and a fastening mechanism for joining together the tapered ends of flue gas conduits.
While this joining connection is satisfactory, it fails to provide air space clearance at the connection between the conduits, makes no provision for indexing of the tab fasteners, has no means for tightening the clamping ring, and does not permit assembly of the conduits without the necessity of rotating the components.
There is a need for a more rigorous vent system which utilizes a joining connection differing substantially from those presently available in the prior art.
The joining connection of the invention employs a tapered joint geometry at the flue gas conduit ends; but, rather than the fastening mechanism of the prior art, a substantially more rigorous mechanical locking system is utilized which comprises shaped, strategically located, locking tabs which provide a means for securing together the conduit ends, and a clamping band or locking ring having slots for capturing the locking tabs and a screw mechanism for tightening the band from a single location, thereby affording fast installation for locking the conduits together.
In one of its embodiments the conduits of the flue gas joining connection of the invention employ a double-wall construction of spaced, concentric, inner and outer walls.
This double-wall construction allows for an insulating blanket of air (or other tangible materials such as fiberglass, mineral wool, etc.) between the inner wall and the outer wall. This air insulation has the advantage of keeping the flue gases warmer, as well as making the skin temperature of the outer wall cooler than would be possible with an uninsulated single-wall section. The reduced skin temperature allows the joining connection of the invention to be installed in closer proximity to combustible materials.